The concept of the composite monarchy as it developed by contemporary historiography, is an effective analytical research tool for study of extensive territorial states with a complex internal structure. This concept clearly demonstrates the diversity of ethnopolitical and ethnocultural processes undergone within such polities in the Early Modern Europe. Composite monarchies had been developed under the persistent impact of the two concurring discourses: the universalistic and particularistic ones. These discourses, in turn, structured the outlines and internal structural boundaries within composite states. The history of Britain in the High Middle Ages and particularly under the Tudors and the early Stuarts evidenced the emergence of so called “composite”(or multiple) identities. Being developed within complex and territorially heterogenous polities, «composite» identities took the form of the so-called consensual identities, associated with the minor regional and local ethnical communities which functioned under the pressure of the composite state. Conditions for several acculturation strategies (assimilation, separation, marginalization and integration) appeared inside of the Late Medieval and Early Modern states but an integration was the only possible way for developing of consensual identity within the composite monarchies. Acculturation allowed to actualize the historical and cultural heritage of the regional and local communities as well as to structure their collective consciences.